Physiological factors that contribute to excellence in the sport of Brazilian Jiu-Jitsu

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Testing Battery for Brazilian Jiu-Jitsu

 

By

 

John Negoescu

 

School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, 6027

ECU School of Medical and Health Sciences

Email: jnegoesc@our.ecu.edu.au

 

Abstract:

 

The aim of this paper is to assess the physiological factors that contribute to excellence in the sport of Brazilian Jiu-Jitsu (BJJ) and to develop a field testing battery in relation to these physical parameters. This battery can be used to guide the direction of the athletes training programs by identifying strengths and weakness, provide feedback to coaches and athletes and provide realistic performance goals. This testing battery will use the most valid and reliable field assessment tools that have been used previously in the assessment of the BJJ population or sports with similar requirements; if this equipment is not readily available a test that has a high correlation (shared variance) will be used. Assessments with less validity or reliability than is sought in the scientific community will be justified. It should be noted that this test is designed to identify physical parameters of bjj athletes, skill, technique and psychological ability are assessed during grading for belts and would be conducted by an expert in that field.

 

Introduction

Brazilian Jiu-jitsu (BJJ) is a unique style of martial arts that is growing in popularity; its origins are from self-defence. Reasons for the growth of popularity include that the system allows smaller and weaker opponents to take down larger stronger opponents by using correct technique, the requirement for strategy and not just physicality and the applicability of core BJJ skills and techniques to other martial arts including Mixed Martial Arts (MMA) (24). During BJJ competitions match times are based on rank (graded from white to black) and weight range, the combats range from 5 minutes for white belts (14) to 10 minutes for black belts (24). Competitions are run in tournament styles with multiple fights occurring over the same or many days. In the championship bout, the time between combat sets are twice the maximum time of combat, for example 20 minutes rest / recovery time for blackbelts(2). There is a prescribed scoring system and points are allocated by a referee, the referee has the power to allocate points and also to terminate the competition if a hold is applied in a way that may cause serious injury (24). Points are allocated for specific BJJ actions such as take downs, passing the guard, knee on the belly, the mount, the back grab, and the sweep(22).

 

Traditionally training for BJJ has mostly consisted of practising the elements typical of combat with opponents and involved movements of pushing, immobilizing, pulling, overthrow, pressing, turning and throttle (5). There is a relative gap research in regards to aspects of BJJ including testing batteries for assessment. Training of athletes has often been based on research generalized from other sport such as judo, this can be problematic, as critical differences exist in aerobic and anaerobic demands across sports, for example there are differences in effort pause ratios and fights are typically of longer duration in BJJ (1, 26). Judo fights are often won as a consequence of throwing techniques whereas BJJ is typically won by grappling technique (2). With the move of BJJ from being predominantly a self defence system to a sport, research efforts have started to centre on evidenced based training protocols(14) . Given the lack of BJJ literature a needs analysis of BJJ is required to identify Physiological parameters of importance as they require to identify assessment strategies, access to equipment and common injury sites will also be considered (23). It is commonly accepted in the literature that elite athletes can perform the same activity as non-elite athletes with physiological and perceptual responses that are slightly lower due to mechanical advantages and better technical skills(2) however limited publications in this area dictate that generalizations need to be made from research with non-elite BJJ athletes to elite BJJ athletes, this will be noted.

 

Anthropometrics and Body Composition

BJJ is divided into nine weight categories, besides the category called absolute. The aim of the weight categories is to provide equitable combat matches between competitors in terms of strength, ability and leverage (6). Identifying the maximal advantageous body composition is an important aspect in a testing battery for BJJ. The development of higher relative levels of lean mass is desirable in the BJJ athlete as to enhance speed, strength and power. Similarly high levels of body fat are detrimental to performance by decreasing the athletes power to weight ratio and possibly even causing the athlete fight in a weight class higher than they should(16).

 

On examination of anthropometric profiles of elite BJJ athletes (national or international level) a predominant mesomorphic component was observed (2), this has also been observed in a review of the Mixed Martial Art published literature (14). A study of brown and black belt BJJ athletes (N=11) revealed that the average body fat percentage was (10.3 +-2.6%) and a lean body mass of (61.3 +-1.5%)(2). Higher level BJJ athletes were compared to lower ranked BJJ athletes had lower fat mass percentage (2). A further study found that body fat percentage  measured over 3 sites (abdomen, triceps, and subscapular) was found to distinguish Elite BJJ athletes (11.2% +-3.0; 95%CI 8.7-13.7)  from non-elite athletes (14.8% +- 3.0 95%CI 17.7-16.9), these differences were associated with performance advantages in the Elite BJJ athletes  (19). Whilst differences in these studies occurred in terms of methodology such as number of sites measured to calculate skin folds and formula to calculate these variables; the studies supported the notion that maximization of the lean body mass was advantageous.

 

Measurement of body composition

The evidence presented is the basis for choosing a skinfolds analysis of bodyfat percentage as the equipment is readily available and relatively inexpensive. It should be noted that skinfold analysis requires a high level of skill in the application of the assesment. The protocol for the assessment is below.

 

“A digital scale was used for the body mass and height measurements. Skinfold measurements were obtained from 7 sites (chest, mid-axillary, suprailiac, abdominal, thigh, triceps, and subscapular) and used in the equation proposed by Jackson and Pollock for estimating the body density. The fat percentage was estimated with the Siri formula

A person with more than 7 years of experience in this type of procedure performed the anthropometric measurements. A coefficient of variation of less than 2% and an intraclass correlation coefficient (ICC) with 0.99 reproducibility were reported between measurements within the assessment performance period.” (10)

 

Changes in anthropometric measures typically reflect the balance of diet, training demands and the strength and conditioning program. Use of the Lean Mass Index may be applied in assessing proportional body mass changes adjusted for skinfold thickness (25) however further research is needed to determine the correct coefficient for that population and the assessment methodology would need to take skinfolds from 9 sites.

 

Flexibility

Flexibility specifically in the trunk and hamstrings is required for BJJ athletes to perform specific movements. While the sit and reach test has moderate validity for the testing of the flexibility of the back and hamstrings it has been used to distinguish between higher and lower level combat athletes (1).The mean score for the sit and reach test for the 11 brown and black belt BJJ athletes was +35 cm (SD +- 8 Range +22 – +52cm) while they showed more flexibility than wrestlers this is considered average for the sport (1, 26). (1) 7 high level bjj athletes Sit and reach 43cm (SD +- 3cm)(12). A further study that compared elite to non-elite BJJ athletes revealed that elite BJJ athletes displayed significantly (t =3.1; p=0.007; d=0.40)  higher levels of flexibility (Elite BJJ 40cm+-3 ;95%CI 37-43cm; Non elite BJJ 32cm+-3 ;95%CI 30-34cm) when evaluated by the sit and reach test (19).

 

flexibility – ICC = 0.98, SEM = 2.1 cm, LOA = -0.6 cm (95% confidence interval = -1.6 to 0.4 cm).

Flexibility. Flexibility was measured using a sit-andreach test. The results are presented in centimeters (cm). The participant sat with knees straight and feet flat on the bench, then inclined his or her trunk forwards as far as possible (Johnson and Nelson, 1979). Three attempts were performed and the maximum inclination was recorded. There was a 1 min interval between attempts (Brown and Weir, 2003). Statistical Analysis Data are presented as mean, stand

Sit and reach (cm) mean 27 SD 8 95%CI 23 – 32 Range 9 – 40

 

 

Injuries / injury prevention

The injury rate of BJJ when compared to MMA was 26 times lower with a rate of 9.2 per 1000 exposures.  Investigation of injuries sustained during state-wide competitions in Hawaii between 2005 and 2011 found that orthopaedic injuries were most common and accounted for 78%of all injuries, with the elbow being the most commonly injured joint. The injury typically occurred from a jiu-jitsu arm bar, next most common was foot and ankle injuries (24). Differences in tactical style revealed a statistically non-significant difference in injuries sustained whereby Guard fighters (used more drive groundwork fight in a supine position) and Pass fighters (they would develop the combat with the knees on the floor, trying to move forward and pass the guard of his opponent, trying to reach the opponent’s side) guard fighters sustained more injuries to the knees due to overload, whereas pass fighters sustained more injuries to their shoulders and elbows. The study found that almost half of the sample had injuries in the upper limbs and a quarter had injuries in the lower limbs in the last year.

 

The FMS is an assessment that could be related to injury incidence and seeks to detect muscular imbalance and movement dysfunction. The FMS was used to assess BJJ athletes. Athletes with lower performances scores than 14 points, were found to have higher rates of injury(4). BJJ athletes fighting styles, (guarding or passing) should still be considered, in the assessment for their risk of injury profile. Previously, it was found that FMS may help to identify weaknesses in muscle groups, and insufficient scores in FMS could be associated with problems in the locomotor system and genesis of sports injuries.  The FMS predicted serious injuries with a specificity of 0.91 and a sensitivity of 0.54 for athletes with  a score of 14 or less on the FMS (4) Boscolo and colleagues sample consisted of 33 practitioners of BJJ (26 men and 7 women) from 3 different schools of Recife, Brazil. Rater reliability was examined for  the overall score analysis in FMS using data from 8 subjects who were not part of the study  (ICC = 0.97; F = 38.1, p , 0.001 and Cronbach’s alpha = 0.9)(4).

 

The procedures adopted by Boscolo and colleagues replicated those of Cook and colleagues and Cook and Burton (7, 8). Each fighter performed 3 attempts in each of the 7 proposed tests sequentially applied. Three global integration testing bodies (deep squat, hurdle step, and inline lunge), followed by 2 mobility tests (shoulder mobility and active straight leg raise), and finally, 2 stability tests (trunk stability pushup and rotary stability) were applied. For each test, the researchers used scores hierarchically.

 

Practical application – FMS and the sit and reach test allows for the short term and long term tracking of an athletes movement quality also identifying injury related weaknesses in specific areas. Differences in a fighters competency will change the requirements of the training program and must be identified by the strength and conditioning coach. A qualitative understanding of the movement patterns of an athlete provides the foundation for individualised exercise programming and prescription. (17)

 

Metabolic specificity

BJJ is classified as a grappling combat sport (22). James and colleagues(15) argued that given the high intensity intermittent activity shared by MMA and BJJ there is potential to impact on spectrum of physiological properties. It is argued that assessment of an athlete’s metabolic qualities may distinguish superior competitors whereby the ability to supply adenosine triphosphate (ATP) to the active muscles via three distinct processes: the enzymatic division of stored phophagens (ATP-phosphocreatine system (ATP-PCr), the anaerobic breakdown of glucose of glycogen, into lactic acid (anaerobic or fast glycolysis) and the combustion of carbohydrates and fats in the presence of oxygen will help define the optimal physiological profile and subsequent training protocols.

 

Fights consist of a series of moves that are characterized as acyclic (5). In BJJ bouts there are three phases; fight in distance (striking), fight with grip (throws) and fight in horizontal position (26) During competitions competitors wear a uniform known as a gi and it is used in various gripping, choking and throwing manoeuvres. The goal is for a competitor to take down his opponent, advance his position and force his opponent to submit by tapping out. The submission of the opponent occurs through the application of a stranglehold or joint locks(22). A typical BJJ match comprises of 170s of activity groundwork: 146 +- 119s, standing combat 25+-17s followed by 13+-6s intervals (1). Effort, pause ratio is the ratio of time spent actively engaging in the required activity versus the rest or inactive period. Andreato and colleagues identified that BJJ has a high effort to pause ratio of 6;1 while high intensity actions lasted 2-5 seconds resulting in a low to high intensity ratio of 8:1 (2). A high effort to pause ratio of 10:1 has been recognised by Del Vecchio . Based on these and other observations elite level BJJ is considered predominately aerobic sport with moderate activation of glycolytic system (2, 5, 12, 14-16, 22). Notable contributions from fast glycolysis were present in simulated BJJ combat matches (14). It should also be noted that while the aerobic system may be the dominant energy system that fights can end very quickly and that the ATP-PCr system supplies high intensity movements that can end fights (19).

 

Andreato and colleagues sought to assess the aerobic capacity of BJJ athletes of an elite level. There sample consisted of 11 BJJ athletes ranked at brown belt or black belt who competed at a national or international level. The study showed that the BJJ athletes were found to have a Vo2max of 49.4 ml/kg per minute (SD +- 3.6 Range 42.0 – 54.0 ml/kg per minute). Aerobic capacity was obtained by the treadmill test following by the Bruce protocol using the equation for active men, this is considered medium according to the American College of Sports Medicine (1). James argued that this was not a valid conclusion and observed that other factors needed to be considered, the longer matches of black belt result in a lower expected VO2 max (aerobic power) and higher anaerobic threshold capacity values.   Furthermore the low high intensity efforts leads moderate and high blood lactate levels in response to 5 minute competitions and 10 minute respectively(14). This evidence presented is the basis for choosing the following tests:

 

  1. Short term test of the ATP-PCr system the 40 yard dash or 36.6m run

This test is a maximal alactic test that can be used to assess the phosphocreatine system, and can be used to indirectly estimate horizontal power (Horizontal Power = force (athletes bodymass) x average velocity (distance / time). This test can be done with minimal equipment and be measured with a stop watch. Stop watches are well correlated with timing gates (r=.098) and can be adjusted to timing gates by the following equation. Electronic timer time (s) = 1.0113 x handheld stopwatch time + 0.2252 (13).

 

  1. Anaerobic capacity test – sport specific butterfly lift test

A protocol to test anaerobic energy demands of BJJ was devised by Villar and colleagues (28). The anaerobic testing protocol was constructed after considering the tactical strategies and demands of the sport. They noted that in simulated BJJ tournaments sweeps accounted for 20-39% of score generating techniques. A sweep is a technique that is used to unbalance, invert and gain a dominant position over the opponent. Sweeping ground techniques require a combination of speed, strength and power derived from anaerobic capacity in BJJ.  The research consisted of simulated combat, in which athletes were matched by weight category and their rank (1 brown belt and 8 black-belt) and execution of a sweep technique, the butterfly lift. Physiological markers were collected to assess heart rate, lactate levels and Rates of Perceived Exertion (RPE).

 

Training was given to athletes on correct execution of the Butterfly lift / sweep.  To execute the lift the BJJ test athlete lay on their back with legs raised, with knees on a 45 degree angle to the floor, scooped between the legs of the second athlete (combat partner). The partner remains seated over the BJJ test athlete, whilst maintaining a straight back. The movement sequence started with the BJJ test athlete performing hip and knee flexion moving to a seated position, whilst wrapping his arms and gripping behind his partner’s back (close to the axilla region). The BJJ test athlete hands remained clasped in a gable grip, with one hand in a pronated position and the other hand is in the supinated position, while the BJJ test athlete’s thorax was pressed to the partner’s thorax. In this exact movement the BJJ test athlete returns to the lying in the supine position with knees flexed performing a kicking motion (knee extension) reaching a 90 degree angle to the floor so as to project the partner over himself. Following this the BJJ test athlete flexed his knees and simultaneously brought his partner back to his original position. Finally the test athlete returned to his initial position lying supine with shoulders hyper-flexed to repeat the same movement cycle. The anaerobic testing session required the execution of five bouts of 1 minute “butterfly lifts”(300 seconds work time), followed by 45 seconds break between bouts(28)

 

Analysis of the data collected during the BJJ anaerobic capacity test, showed that for 8 of the athletes the maximal number of butterfly lifts occurred at the second bout (17.4+-1.3 repetitions), then dropping significantly in the fourth and fifth bouts (p<.05) with increases in lactate, heart rate and rate of perceived exertion. The decline in the number of butterfly lifts was argued to be a consequence of the high metabolic acidosis caused by progressive lactate accumulation. The effort pause ratio of the butterfly test was sufficient to promote energy production via activation of the glycolytic metabolic pathway. Heart rates of athletes when performing the butterfly lift test were in the ranges of heart rates observed in BJJ 2005 world cup (12). The butterfly lift protocol was considered a valid testing protocol to assess the performance in BJJ athletes.

 

This specific BJJ anaerobic test can be used across all phases of training phases, the information gathered would support physical conditioning coaches and guide best practices supporting modifications in volume and intensity in phases of the periodisation cycle (28).

 

  1. Aerobic power – 20-meter shuttle test

The 20 meter shuttle test is a reliable test of aerobic capacity that requires minimal equipment. It should be noted that in comparison to the Bruce protocol the shuttle run test will give a lower prediction of VO2max than the treadmill protocol, however the two have a high correlation of (r=0.90) (3). The athletes MAS score can also be established from this test and an appropriate interval training plan established.

 

Practical – test results presumably reflect endurance of athletes. Athletes who see to improve aerobic fitness should undertake additional endurance training in the form of interval running or skill based conditioning games. However, it should be noted that excessive endurance training can negatively impact strength, speed and power attributes.

 

Neuromuscular specificity / movement patterns / contractile specificity

Strength is the ability of the neuromuscular system to produce force against an external resistance(27). Strength and muscular power are intimately related. It has been shown that stronger people are able to produce higher power outputs in loaded and unloaded conditions (9). Higher levels of absolute strength and power is required to apply high forces quickly in contact situations and differentiates between higher and lower level rugby league players who experience grappling demands as in BJJ (18). In addition to maximal strength being a potential marker these athletes it positively impacts on physiological capabilities, that allows superior adaptation to power training (14). Power is associated with explosive movements that allow the grappler to control their opponent and is a critical predictor of success in judo and BJJ athletes(10) (26). Increased strength also enhances endurance performance and improves resilience to injury (14).

 

For grappling combat sports maximal power is considered important for groundwork techniques when athlete is trying to perform or escape from an immobilization technique. Da Silva and colleagues conducted an experimental study to determine the load for peak power output for BJJ athletes. The athletes were allocated to two groups based on their belt ranks, the advanced group were black and brown belts, the non-advanced group were purple and blue belt. Results showed that the higher rank elite BJJ athletes were stronger (115kg +- 16 1RM) than the less experienced lower rank BJJ athletes (101kg +-13 1RM) when performing the bench press 1RM (10) The optimal load (%of IRM) for development of maximal power was ~ 42% IRM in BJJ athletes: PPO (30-60% IRM) did not differ between higher rank than lower rank BJJ athletes. It was concluded that given some manoeuvres in BJJ are performed on the ground, bench press maximal strength could be more specific for groundwork manoeuvres. (10)

 

Another comparison in strength between elite BJJ athletes and non elite tested the bench press and squat one repetition maximum (1-RM) tests.  Elite BJJ athletes presented better performance in absolute 1-RM bench press test, but not in the squat. (Elite Group: 111 kg ±6 (106—116) Relative 1.46 ± 0.13 kg/kg, Non-elite Group: 98 kg ±6 (94—102) 1.36 ± 0.11 kg/kg, P = 0.096, d = 0.40) and squat (EG: 88 kg ±7 (83—93) Relative: 1.20 ±0.13 kg/kg, NEG: 1.23± 0.13 kg/kg, P = 0.700, d = 0.23) (19).

 

As a grappling sport BJJ athletes were seen to need high levels of upper body strength (23). Isometric strength is considered important for BJJ athletes as the sport requires extreme contact and does not allow much space for dynamic movement. Whilst non elite BJJ athletes were found to have lower maximal back strength than Judokatas a high level of maximal isometric back was observed in Elite BJJ athletes (m=185;SD 36) (1).

 

Submission holds require the ability to maintain hold on the opponent’s uniform, hand grip strength was therefore hypothesised to be a potentially important variable. On investigation Andreato and colleagues found that BJJ athletes do not reveal substantial handgrip strength (1). When investigating physiological factors that predict performance in BJJ athletes Andreato and colleagues noted that maximum isometric strength was not an important characteristic of BJJ athletes it was ability to maintain a high percentage of maximum handgrip till the end of a fight. (2). The data suggest that isometric hand endurance strength is a valid predictor of performance in BJJ. It should be noted that increasing hand grip strength will decrease the total percentage of grip strength that is applied and may increase endurance performance.

The Kimono Pull Up test is considered a test of dynamic and isometric strength endurance, and was able to track improvement in isometric grip performance for BJJ athletes post training. This study examined the difference in performance between Advanced BJJ athletes (brown or black belts and state, national or international medallists), Non Advanced BJJ athletes (blue or purple belt state, national or international medallists) Recreational BJJ athletes and Beginner BJJ athletes. The dynamic kimono grip pull up test showed that the maximal number of repitions were significantly different for the Advanced group compared to recreational and beginner BJJ athletes but not the Non Advanced group. The dynamic lift did however discriminate strength endurance across differrent combat sports whereby BJJ athletes outperformed Judo athletes(11)

 

The evidence presented is the basis for choosing the following tests.

 

  1. Strength – 1RM Back Squat , 1RM Bench Press, 1RM Clean

1RM retest reliability for the bench press and the back squat of (0.94 – 0.99).

Subjects performed a specific warm-up set of 5 repetitions at approximately 50% of the estimated 1-RM followed by another set of 3 repetitions at 70% of the estimated 1-RM, separated by 2 min interval. Then, athletes were submitted to the 1-RM test and carried out at least three and at most five trials, with 3 to 5 mins intervals between them, following the recommendations made by Brown and Weir The procedures proposed by Pollock and Wilmore were adopted for all test (19).

 

  1. Power – Static Jump, Counter Movement Jump,

The counter movement jump test provides a useful field based measure of leg power. Countermovement jump test results can compared to previous results. Improvements in jump height can reflect an improvement in lower body muscular power, jumping technique, timing and coordination. The static jump does not utilise the stretch shortening cycle and it is established that CMJ height will be greater than that of the SJ, if this is not the case it may be an indication of a poor usage of the SSC. (21)

The reliability among all jumping tests had an ICC of SJ 0.97 CMJ 0.98 SLJ 0.95 .(20)

Vertical displacement (cm) = Jump height (cm) – Reach Height (cm)

Sayers equation: Peak power = 60.7 x jump height (cm) + 45.3 x bodymass(kg) – 2055

 

 

  1. Strength endurance / local muscular endurance – max pullups kimono grip

The Kimono Pull Up test consist of maximum number of repitions performed on a task . The Kimono Pull Up Test , is used to attain maximum number of repitions performed, and consisted of Advanced and non advanced BJJ completing the Maximum number of repetitions (MNR) , 15 minutes after the Maximum Static Lift test (this test was not found to discriminate performance across training levels and therefore not used), the protocol for the MNR involved cycling for 3-min and completion of two sets of five repetitions with 1-min break. Following 3-min of passive pause, the athletes performed the MNR from a fully flexed to a fully extended elbow position.

The reliability for the MNR test was assess ed in a previous study, with an intraclass correlation coefficient (ICC) > 0.9 and a confidence interval 95% inferior/superior limits of 0.927/0.989 and 0.966/0.995. Both in the familiarization and in the days of the tests the participants were instructed to arrive at the gym in a rested and fully hydrated state, at least 4-hr postprandial, and to avoid strenuous exercise in the previous 24h. Each subject was tested at the same period of the day (16:00 h – 18:00 h) in a room with constant temperature (23 ºC) (da Silva et al 2014).

 

  1. Sit up test Justification

Abdominal muscle strength endurance is an important variable in BJJ due to combat dynamics which involve constant movement from the hip. The one minute sit-up test was found to distinguish elite and non elite BJJ athletes(19).

 

Recomendations:

Significant difference between elite and non-elite groups were identified for body composition, maximal absolute strength in the bench press, flexibility, upper limbs and abdominal strength endurance, indicating that the development of these variables can contribute to the improvement of performance in this sport. Additional longitudinal studies must be conducted to determine how much the improvement in these and other variables with potential contribution to performance may effectively result in improved performance in this sport. Moreover, the relationship of these characteristics with technical-tactical actions (e.g. techniques used, time of combat on the ground and standing positions, and number of effective techniques) performed during the match needs to be investigated.

While this is a physical testing battery for BJJ athletes more research should be conducted on the development of open based skill testing which require an external input which will help determine speed and ability of fighters to read their opponent and make the correct decision for that situation.

 

 

Testing battery (the testing battery is presented in the order that it would be conducted so there is minimal interference between tests.)

 

  • Non fatiguing tests
    • Anthropometry – height and weight
    • Skinfold testing. 7 sites
    • Flexibility – FMS and sit and reach

 

  • Maximal power (min 3-5 minutes rest for complete recovery)
    • Countermovement jump
    • static jump

 

  • Short term anaerobic test (min 3-5 minutes rest for complete recovery )
    • 40 yard / 36.6m

 

  • Maximal strength and power (min 3-5 minutes rest for complete recovery)
    • 1RM testing

 

  • Local muscular endurance test Strength endurance (min 3-5 minutes rest for complete recovery)
    • Grip strength
    • Upperbody strength

 

  • Fatiguing anaerobic capacity tests (take 1 hour for recovery)
    • Butterfly lift test

 

  • Aerobic capacity tests
    • 20 meter shuttle test

 

 

 

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